For good reason, Neem oil has long been touted as one of the best all-natural treatment options for pest management on houseplants. When applied correctly, it does a great job knocking back an infestation within a matter of weeks. But are there any risks associated with its use? Is Neem really safe to use on houseplants?
Neem oil is a natural substance derived from the seeds of Neem trees and works as an effective pesticide on indoor houseplants. When used correctly, there are very few risks to the plant, and it is typically very safe to use around adults, children, and pets.
When used correctly, Neem oil is a very effective pesticide that quickly and efficiently controls for a variety of common houseplant pests. Like with any product, there are a few risks associated with its use, but most are very minor and only an issue when Neem oil is applied at the wrong strength.
In this article, we’ll cover the few risks associated with Neem oil use to get a better understanding of the importance of mixing and applying it properly.
What Is Neem Oil?
Neem oil is a natural material produced by pressing the seeds and fruit of the Neem tree (Azadirachta Indica), a variety that grows in and around India. This oil contains many different chemical compounds that act as natural pesticides and fungicides.
Most commonly, pure Neem oil is mixed with water and then sprayed onto a plant to coat stem and leaf surfaces, as well as any bugs residing on those structures.
The main compound in Neem oil, called Azadirachtin, has been shown to disrupt certain hormones responsible for the growth of many different insects and suppress appetites to a point where they will starve to death.
Also, because it is an oil, its thick, sticky texture does an excellent job of coating insects and blocking respiratory structures, causing the bugs to suffocate.
It works on a plethora of different insect and mite species, including aphids, thrips, spider mites, mealybugs, scale, whiteflies, and many others.
How to Apply Neem Oil
Neem oil is most often mixed as a solution with water and applied to plants as a spray. This is because, in order to work, it needs to come in contact with the bugs residing on a plant, and spraying provides the best coverage.
There are many ready-to-use Neem products available on the market that are a good option for people who don’t want to mess with mixing their own formulations. However, these are often made with oil derivatives that tend to be less potent than pure Neem oil.
For better results, look to purchase pure, cold pressed Neem oil and mix it into the solution yourself. It will contain a higher concentration of the natural chemical compounds you need for better control, which means you will likely use less product overall.
A good starting point is to create a mixture that is roughly one ounce of pure Neem oil to a gallon of water. Most plants can handle this strength easily, and it minimizes any risk of damaging plant structures. Adding a small amount of natural dish soap acts as an emulsifier to keep the oil in solution.
To make a quart of Neem oil solution, the recipe breaks down to 1½ teaspoons of Neem oil, ½ teaspoon of dish soap, and 32 ounces of water.
Place this mixture into a spray bottle or mister, and spray your houseplant liberally, making sure to cover all surfaces, especially the undersides of leaves and the crooks of stems. You need to make sure you are coating any bugs in the solution in order to kill them.
Neem oil is effective, but you’ll likely need to repeat applications about once a week until all signs of the pest infestation are gone.
There is much more to learn about Neem oil and its many uses. We’ve written an article that allows you to take a deeper dive into how Neem oil works. We discuss how to buy and store it, and most importantly, how to mix and apply it correctly.
What Are the Risks Associated with Neem Oil?
When applied correctly, Neem oil is very safe to use on most plants and does not have any negative side effects for people or pets. If mixed too strong or applied incorrectly, you do run the risk of some potential damage to your houseplant, but these risks are minor and easily avoidable.
Can Neem Oil Kill Plants?
Like with all pesticides, if you apply Neem oil incorrectly, you do run the risk of causing harm and damage to your houseplant. However, because it is such a low-impact, natural substance, Neem oil grants you a little extra grace during those times when you may have accidentally mixed a solution a bit too strongly.
Therefore, it is very unlikely that Neem oil alone can kill your houseplant. There are situations where Neem oil can cause damage to a plant, but it is very rarely severe enough that your plant will succumb due to any of these injuries.
However, it’s probably best not to test your plant’s limits with Neem oil, so make sure you follow the above recipe and adjust the strength if you are dealing with a particularly sensitive or tender plant.
Can Neem Oil Burn Leaves?
One of the minor risks associated with Neem oil is that it has the potential to burn certain varieties of plants, mainly when it is applied to a plant that is exposed to a lot of sunlight.
As Neem oil coats plant surfaces, the strength of the sun’s light (especially direct light) can be magnified by the shiny liquid, causing the leaves to burn.
This is usually pretty easy to avoid. When applying Neem oil to a plant, either pull it back from a light source or spray it during the morning or evening, when sunlight and heat are less intense.
What Plants Should Neem Oil Not Be Applied To?
Again, Neem oil is a great product to use on most houseplants as a pest-management treatment. However, there are some plants that are more susceptible to negative side effects in the event you either overapply or mix your Neem oil solution too strongly.
Plants with delicate or frilly leaf structures, like ferns, tend to be less forgiving if exposed to too much Neem oil. African Violets, Rex Begonias, or other plant types that sport hairy or fuzzy leaves can also be more susceptible to Neem oil residue buildup, potentially causing some health issues.
Within certain types of plants, tolerance to Neem oil can vary widely across varieties. For example, many orchid and succulent varieties do very well with Neem oil applications, while others can be rather finicky. If you are unsure if your variety will handle it well, it’s best to test a small area on the plant first.
Should I Spray New Plants with Neem Oil?
In general, any new or recently transplanted houseplants are already more sensitive to any type of treatment, including Neem oil. Most of their energy is going towards reestablishing themselves in their new pots, and they may even be experiencing some temporary distress while they root out.
Hopefully, any new plants you have do not fall prey to pests, but if they do, it is advisable to wait until they are more established before using Neem oil or any other spray treatment. Instead, utilize different methods of physical removal until they are big enough to handle a Neem oil application.
Is Neem Oil Safe for Pets?
One of the best qualities about Neem oil is how safe it is to use in your home. This means that, when applied correctly, there are almost no risks to adults, young children, or household pets.
Neem oil can cause skin sensitives or digestive distress if touched or swallowed, but those symptoms generally occur at higher concentrations. For the most part, if you’ve applied a diluted mixture of Neem oil on your houseplants, pets are at very low risk for any ill side effects, especially once it has dried on the plant.
Does Neem Oil Kill Beneficial Insects?
One important concern with any pesticide product is how it affects all the good bugs that help our plants. Bees and other pollinators are important parts of our ecosystem, and there are plenty of beneficial insects, like ladybugs, that like to feed on the pesky pests we are trying to get rid of.
Neem oil is a great product that can target a lot of the bad bugs without impacting all the good ones we want around. However, how you choose to apply it has a lot to do with how much you can minimize collateral damage. In the context of houseplants, you are usually fine to apply Neem oil as you see fit. Beneficial insects aren’t usually a huge factor inside our homes, so you really don’t need to worry much about them.
However, if you are treating any houseplants outdoors, or you have a collection of plants that live outside during the warmer months, you will want to pay attention to how you apply Neem oil.
Bees and other pollinators are usually attracted to plants because of their nectar, and most tend to do most of their searching during the day. Because of this, try to apply Neem oil to plants early in the morning or later in the evening to minimize exposure to the number of active pollinators visiting the plant.
Ladybugs tend to be unaffected by Neem oil as long as they aren’t directly doused in it. When applying it to plants, again try to do so in the morning or evening, when ladybugs and other beneficial insects are less active, and try to avoid direct contact with them, if possible.
Final Thoughts
As you can see, the list of risks associated with Neem oil is rather short, which is why it is such a popular method of pest control, both indoors and out. By following the proper mixing instructions and applying it correctly, you can easily avoid any negative side effects. Not only will your plant be healthy, strong, and pest-free, but you will have minimized the impact on people and pets and the beneficial insects that live around your home.